Cardiopulmonary resuscitation in special circumstances.

Cardiopulmonary resuscitation prioritises treatment for cardiac arrests from a primary cardiac cause, which make up the majority of treated cardiac arrests. Early chest compressions and, when indicated, a defibrillation shock from a bystander give the best chance of survival with a good neurological status. Cardiac arrest can also be caused by special circumstances, such as asphyxia, trauma, pulmonary embolism, accidental hypothermia, anaphylaxis, or COVID-19, and during pregnancy or perioperatively. Cardiac arrests in these circumstances represent an increasing proportion of all treated cardiac arrests, often have a preventable cause, and require additional interventions to correct a reversible cause during resuscitation. The evidence for treating these conditions is mostly of low or very low certainty and further studies are needed. Irrespective of the cause, treatments for cardiac arrest are time sensitive and most effective when given early-every minute counts.

Conservation resource allocation, small population resiliency, and the fallacy of conservation triage.

Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.

Asignación de Recursos para la Conservación, Resiliencia de Poblaciones Pequeñas y la Falacia del Triaje de Conservación Resumen Algunos métodos de priorización de la conservación están basados en el supuesto de que las necesidades de la conservación superan a los actuales recursos y que no todas las especies pueden ser conservadas; por lo tanto, se necesita un esquema de triaje (esto es, cuando el sistema está abrumado, las especies deben dividirse en tres grupos con base en su probabilidad de supervivencia y los esfuerzos deben enfocarse en aquellas especies dentro del grupo con las mejores probabilidades de supervivencia y a aquellas en el grupo sin probabilidades de supervivencia o aquellas en el grupo que no necesita esfuerzos especializados para su conservación se les deben reducir o negar los esfuerzos de conservación) para dirigir la asignación de recursos. Discutimos que esta estrategia para la toma de decisiones no es apropiada porque los recursos no están tan limitados como se asume con frecuencia y tampoco es evidente que existan especies que no puedan ser conservadas. Por ejemplo, tan sólo un tamaño poblacional pequeño no es suficiente para condenar a una especie a la extinción; contamos con ejemplos en plantas, reptiles, aves y mamíferos. Aunque actualmente todos los recursos dedicados a la conservación de todas las especies amenazadas son insuficientes, los recursos económicos mundiales son vastos y se podrían dedicar mayores recursos a la conservación de especies. El marco de trabajo político para la conservación de especies ha mejorado, con iniciativas como los Objetivos de Desarrollo Sustentable de la ONU y otros acuerdos internacionales, el financiamiento de mecanismos como el Fondo para el Medio Ambiente Mundial, y el surgimiento de muchas organizaciones no gubernamentales mediante programas de subsidios pequeños hábiles y de respuesta rápida. Para que un sistema de priorización no permita las extinciones, las cero extinciones deben ser un objetivo explícito del sistema. La extinción no es inevitable y no debería ser aceptable. El objetivo de cero extinciones inducidas por humanos es imperativo dada la irreversibilidad de la pérdida de especies.

Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations.

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.

Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations.

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.

Frailty, delirium and hospital mortality of older adults admitted to intensive care: the Delirium (Deli) in ICU study.

BACKGROUND: Clinical frailty among older adults admitted to intensive care has been proposed as an important determinant of patient outcomes. Among this group of patients, an acute episode of delirium is also common, but its relationship to frailty and increased risk of mortality has not been extensively explored. Therefore, the aim of this study was to explore the relationship between clinical frailty, delirium and hospital mortality of older adults admitted to intensive care. METHODS: This study is part of a Delirium in Intensive Care (Deli) Study. During the initial 6-month baseline period, clinical frailty status on admission to intensive care, among adults aged 50 years or more; acute episodes of delirium; and the outcomes of intensive care and hospital stay were explored. RESULTS: During the 6-month baseline period, 997 patients, aged 50 years or more, were included in this study. The average age was 71 years (IQR, 63-79); 55% were male (n = 537). Among these patients, 39.2% (95% CI 36.1-42.3%, n = 396) had a Clinical Frailty Score (CFS) of 5 or more, and 13.0% (n = 127) had at least one acute episode of delirium. Frail patients were at greater risk of an episode of delirium (17% versus 10%, adjusted rate ratio (adjRR) = 1.71, 95% confidence interval (CI) 1.20-2.43, p = 0.003), had a longer hospital stay (2.6 days, 95% CI 1-7 days, p = 0.009) and had a higher risk of hospital mortality (19% versus 7%, adjRR = 2.54, 95% CI 1.72-3.75, p < 0.001), when compared to non-frail patients. Patients who were frail and experienced an acute episode of delirium in the intensive care had a 35% rate of hospital mortality versus 10% among non-frail patients who also experienced delirium in the ICU. CONCLUSION: Frailty and delirium significantly increase the risk of hospital mortality. Therefore, it is important to identify patients who are frail and institute measures to reduce the risk of adverse events in the ICU such as delirium and, importantly, to discuss these issues in an open and empathetic way with the patient and their families.

Afferent limb failure revisited - A retrospective, international, multicentre, cohort study of delayed rapid response team calls.

AIM: The efficiency of rapid response teams (RRTs) is decreased by delays in activation of RRT (afferent limb failure, ALF). We categorized ALF by organ systems and investigated correlations with the vital signs subsequently observed by the RRT and associations with mortality. METHODS: International, multicentre, retrospective cohort study including adult RRT patients without treatment limitations in 2017-2018 in one Australian and two Finnish tertiary hospitals. RESULTS: A total of 5,568 RRT patients' first RRT activations were included. In 927 patients (17%) ALF was present within 4 h before the RRT call, most commonly for respiratory criteria (419 patients, 7.5%). In 3516 patients (63%) overall, and in 756 (82%) of ALF patients, the RRT observed abnormal vital signs upon arrival. The organ-specific ALF corresponded to the RRT observations in 52% of cases for respiratory criteria, in 60% for haemodynamic criteria, in 55% for neurological criteria and in 52% of cases for multiple organ criteria. Only ALF for respiratory criteria was associated with increased hospital mortality (OR 1.71, 95% CI 1.29-2.27), whereas all, except haemodynamic, criteria at the time of RRT review were associated with increased hospital mortality. CONCLUSIONS: Vital signs were rarely normal upon RRT arrival in patients with ALF, while organ-specific ALF corresponded to subsequent RRT observations in just over half of cases. Our results suggest that systems mandating timely responses to abnormal respiratory criteria in particular may have potential to improve deteriorating patient outcomes.

Advanced airway management during adult cardiac arrest: A systematic review.

AIM: To systematically review the literature on advanced airway management during adult cardiac arrest in order to inform the International Liaison Committee of Resuscitation (ILCOR) consensus on science and treatment recommendations. METHODS: The review was performed according to PRISMA guidelines and registered on PROSPERO (CRD42018115556). We searched Medline, Embase, and Evidence-Based Medicine Reviews for controlled trials and observational studies published before October 30, 2018. The population included adult patients with cardiac arrest. Two investigators reviewed studies for relevance, extracted data, and assessed the risk of bias of individual studies. RESULTS: We included 78 observational studies and 11 controlled trials. Most of the observational studies and all of the controlled trials only included patients with out-of-hospital cardiac arrest. The risk of bias for individual observational studies was overall assessed as critical or serious, with confounding and selection bias being the primary sources of bias. Three of the controlled trials, all published in 2018, were powered for clinical outcomes with two comparing a supraglottic airway to tracheal intubation and one comparing bag-mask ventilation to tracheal intubation. All three trials had some concerns regarding risk of bias primarily due to lack of blinding and variable adherence to the protocol. Clinical and methodological heterogeneity across studies, for both the observational studies and the controlled trials, precluded any meaningful meta-analyses. CONCLUSIONS: We identified a large number of studies related to advanced airway management in adult cardiac arrest. Three recently published, large randomized trials in out-of-hospital cardiac arrest will help to inform future guidelines. Trials of advanced airway management during in-hospital cardiac arrest are lacking.

2018 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations Summary.

The International Liaison Committee on Resuscitation has initiated a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation science. This is the second annual summary of International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations that includes the most recent cardiopulmonary resuscitation science reviewed by the International Liaison Committee on Resuscitation. This summary addresses the role of antiarrhythmic drugs in adults and children and includes the Advanced Life Support Task Force and Pediatric Task Force consensus statements, which summarize the most recent published evidence and an assessment of the quality of the evidence based on Grading of Recommendations, Assessment, Development, and Evaluation criteria. The statements include consensus treatment recommendations approved by members of the relevant task forces. Insights into the deliberations of each task force are provided in the Values and Preferences and Task Force Insights sections. Finally, the task force members have listed the top knowledge gaps for further research.

2018 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations Summary.

The International Liaison Committee on Resuscitation has initiated a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation science. This is the second annual summary of International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations that includes the most recent cardiopulmonary resuscitation science reviewed by the International Liaison Committee on Resuscitation. This summary addresses the role of antiarrhythmic drugs in adults and children and includes the Advanced Life Support Task Force and Pediatric Task Force consensus statements, which summarize the most recent published evidence and an assessment of the quality of the evidence based on Grading of Recommendations, Assessment, Development, and Evaluation criteria. The statements include consensus treatment recommendations approved by members of the relevant task forces. Insights into the deliberations of each task force are provided in the Values and Preferences and Task Force Insights sections. Finally, the task force members have listed the top knowledge gaps for further research.

Technology meets tradition: The perceived impact of the introduction of information and communication technology on ward rounds in the intensive care unit.

BACKGROUND: Public policy in many health systems is currently dominated by the quest to find ways to 'do more with less'-to achieve better outcomes at a reduced cost. The success or failure of initiatives in support of this quest are often understood in terms of an adversarial dynamic or struggle between the professional logics of medicine and of management. Here, we use the case of the introduction of information and communication technology (ICT) to a well-established ritual of medical autonomy (the medical ward round) to articulate a more nuanced explanation of how and why new ways of working with technology are accepted and adopted (or not). METHODS: The study was conducted across four intensive care units (ICUs) in major teaching hospitals in Sydney, Australia. Using interviews, we examined 48 doctors' perceptions of the impact of ICT on ward round practice. We applied the concept of institutional logics to frame our analysis. Interview transcripts were analysed using a hybrid of deductive and inductive thematic analysis. RESULTS: The doctors displayed a complex engagement with the technology that belies simplistic characterisations of medical rejection of managerial encroachment. In fact, they selectively welcomed into the ward round aspects of the technology which reinforced the doctor's place in the healthcare hierarchy and which augmented their role as scientists. At the same time, they guarded against allowing managerial logic embedded in ICT to de-emphasise their embodied subjectivity in relation to the patient as a person rather than as a collection of parameters. CONCLUSION: ICT can force the disruption of some aspects of existing routines, even where these are long-established rituals. Resistance arose when the new technology did not fit with the 'logic of care'. Incorporation of the logic of care into the design and customisation of clinical information systems is a challenge and potentially counterproductive, because it could attempt to apply a technological fix to what is essentially a social problem. However, there are significant opportunities to ensure that new technologies do not obstruct doctors' roles as carers nor disrupt the embodied relationship they need to have with patients.

Deliberate employment of postoperative hypotension for brain arteriovenous malformation surgery and the incidence of delayed postoperative hemorrhage: a prospective cohort study.

OBJECTIVE The aim of this study was to examine the impact of deliberate employment of postoperative hypotension on delayed postoperative hemorrhage (DPH) for all Spetzler-Ponce Class (SPC) C brain arteriovenous malformations (bAVMs) and SPC B bAVMs ≥ 3.5 cm in diameter (SPC B 3.5+). METHODS A protocol of deliberate employment of postoperative hypotension was introduced in June 1997 for all SPC C and SPC B 3.5+ bAVMs. The aim was to achieve a maximum mean arterial blood pressure (BP) ≤ 70 mm Hg (with cerebral perfusion pressure > 50 mm Hg) for a minimum of 7 days after resection of bAVMs (BP protocol). The authors compared patients who experienced DPH (defined as brain hemorrhage into the resection bed that resulted in a new neurological deficit or that resulted in reoperation during the hospitalization for microsurgical bAVM resection) between 2 periods (prior to adopting the BP protocol and after introduction of the BP protocol) and 4 bAVM categories (SPC A, SPC B 3.5- [that is, SPC B < 3.5 cm maximum diameter], SPC B 3.5+, and SPC C). Patients excluded from treatment by the BP protocol were managed in the intensive care unit to avoid moderate hypertensive episodes. The pooled cases of all bAVM treated by surgery were analyzed to identify characteristics associated with the risk of DPH. These identified characteristics were then examined by multiple logistic regression analysis in both SPC B 3.5+ and SPC C cases. RESULTS From a cohort of 641 bAVMs treated by microsurgery, 32 patients with DPH were identified. Of those, 66% (95% CI 48-80) had a permanent new neurological deficit with a modified Rankin Scale score of 2-6. This included a mortality rate of 13% (95% CI 4.4-29). The BP protocol was used to treat 162 patients with either SPC B 3.5+ or SPC C. For SPC B 3.5+, there was no significant reduction in DPH with the introduction of the BP protocol (p = 0.77). For SPC C, there was a significant (p = 0.035) reduction of DPH from 29% (95% CI 13%-53%) to 8.2% (95% CI 3.2%-18%) associated with the introduction of the BP protocol. Multiple logistic regression analysis found that the absence of the BP protocol (p = 0.011, odds ratio 7.5, 95% CI 1.6-36) remained significant for the development of DPH in patients with SPC C bAVMs. CONCLUSIONS Treating patients with SPC C bAVMs with a protocol that lowers BP immediately after resection seems to reduce the risk of DPH. For SPC A and SPC B 3.5- bAVMs, there is unlikely to be a need to do more than avoid postoperative hypertension. For SPC B 3.5+ bAVMs, a larger number of patients would be required to test the absence of benefit of the BP protocol.

The importance and benefits of species.

Humans depend on biodiversity in myriad ways, yet species are being rapidly lost due to human activities. The ecosystem services approach to conservation tries to establish the value that society derives from the natural world such that the true cost of proposed development actions becomes apparent to decision makers. Species are an integral component of ecosystems, and the value they provide in terms of services should be a standard part of ecosystem assessments. However, assessing the value of species is difficult and will always remain incomplete. Some of the most difficult species' benefits to assess are those that accrue unexpectedly or are wholly unanticipated. In this review, we consider recent examples from a wide variety of species and a diverse set of ecosystem services that illustrate this point and support the application of the precautionary principle to decisions affecting the natural world.

Hospital outcomes associated with introduction of a two-tiered response to the deteriorating patient.

BACKGROUND: Liverpool Hospital introduced the medical emergency team system in 1990 and it has recently been adopted at a national and international level. New South Wales, Australia, has introduced a standardised rapid response system in over 250 acutecare hospitals: the two-tiered (clinical review call [CRC] and rapid response call [RRC]) "between the flags" (BTF) program. OBJECTIVES: To describe the effect of the introduction of a twotiered response to the deteriorating patient on the number of RRCs, cardiac arrests and hospital deaths. METHODS: Our study was undertaken at an 850-bed teaching hospital in the south-west of Sydney, Australia, with about 80 000 hospital admissions each year. Rates of RRCs, cardiac arrests and all hospital deaths (with and without not-for-resuscitation orders) were compared before the introduction of the BTF program (2009) and after implementation, until June 2013. The rates of CRCs after implementation were measured. Changes in the reasons for RRCs were also compared for the 12-month period before and the 36 months after the introduction of the BTF program. RESULTS: The monthly rate of RRCs before introduction of the program was 18.8 per 1000 hospital admissions (95% CI, 17.8- 19.8 per 1000 admissions) and was estimated to increase by 4% after program implementation (95% CI, 3.2%-4.7%; P < 0.001). The rate of CRCs increased by 13.2% (95% CI, 10.9%-15.6%) during the study period. The cardiac arrest rate before implementation of clinical review was 1.1 per 1000 admissions (95% CI, 0.9-1.3 per 1000 admissions) and after implementation was estimated to have changed by 1% (95% CI, - 1.9 to 3.9; P = 0.48). The hospital death rate before implementation of the BTF program was 10.8 per 1000 admissions (95% CI, 10.1-11.5 per 1000 admissions), and after implementation was estimated to increase by 2% (95% CI, 1.2%-3%, P < 0.001). The reasons for RRCs before and after the introduction of the BTF program did not change (all P values > 0.2), apart from the "worried" criterion, that decreased from 30% to 17% of all calls after implementation (P < 0.001). CONCLUSION: After introduction of the BTF program, there was a progressive increase in documented CRCs and an increase in RRCs. There was no decrease in cardiac arrests or hospital deaths. RRCs based on objective physiological criteria increased. More research is needed to evaluate two-tiered response systems.

Characteristics and outcomes of patients admitted to ICU following activation of the medical emergency team: impact of introducing a two-tier response system.

OBJECTIVE: To determine the impact of introducing a two-tier system for responding to deteriorating ward patients on ICU admissions after medical emergency team review. DESIGN: Retrospective database review before (2006-2009) and after (2011-2013) the introduction of a two-tier system. SETTING: Tertiary, university-affiliated hospital. PATIENTS: A total of 1,564 ICU admissions. INTERVENTIONS: Two-tier rapid response system. MEASUREMENTS AND MAIN RESULTS: The median number of medical emergency team activations/1,000 hospitalizations increased from 22 to 31 (difference [95% CI], 9 [5-10]; p<0.0001) with a decreased rate of medical emergency team activations leading to ICU admission (from median 11 to 8; difference [95% CI], 3 [3-4]; p=0.03). The median proportion of medical emergency team reviews leading to ICU admission increased for those triggered by tachypnoea (from 11% to 15%; difference [95% CI], 4 [3-5]; p<0.0001) and by hypotension (from 27% to 43%; difference [95% CI], 15 [12-19]; p<0.0001) and decreased for those triggered by reduced level of consciousness (from 20% to 17%; difference [95% CI], 3 [2-4]; p<0.0001) and by clinical concern (from 18% to 9%; difference [95% CI], 10 [9-13]; p<0.0001). The proportions of ICU admissions following medical emergency team review did not change significantly for tachycardia, seizure, or cardiorespiratory arrest. The overall ICU mortality for admissions following medical emergency team review for tachypnoea, tachycardia, and clinical concern decreased (from 29% to 9%: difference [95% CI], 20 [11-29]; p<0.0001) but did not change for the other triggers. The Acute Physiology and Chronic Health Evaluation predicted and observed ICU mortality and the proportion of patients dying with a not-for-resuscitation order decreased. CONCLUSIONS: The introduction of a two-tier response to clinical deterioration increased ICU admissions triggered by cardiorespiratory criteria, whereas admissions triggered by more subjective criteria decreased. The overall ICU mortality for patients admitted following medical emergency team review decreased, suggesting that the two-tier system led to earlier recognition of reversible pathology or a decision not to escalate the level of care.

Prevalence and factors correlating with hyperoxia exposure following cardiac arrest--an observational single centre study.

PURPOSE OF THE STUDY: Arterial hyperoxia during care in the intensive care unit (ICU) has been found to correlate with mortality after cardiac arrest (CA). We examined the prevalence of hyperoxia following CA including pre-ICU values and studied differences between those exposed and those not exposed to define predictors of exposure. MATERIALS AND METHODS: A retrospective analysis of a prospectively collected cohort of cardiac arrest patients treated in an Australian tertiary hospital between August 2008 and July 2010. Arterial blood oxygen values and used fractions of oxygen were recorded during the first 24 hours after the arrest. Hyperoxia was defined as any arterial oxygen value greater than 300 mmHg. Chi-square test was used to compare categorical data and Mann-Whitney U-test to continuous data. Statistical methods were used to identify predictors of hyperoxia exposure. RESULTS: Of 122 patients treated in the ICU following cardiac arrest 119 had one or several arterial blood gases taken and were included in the study. Of these, 49 (41.2%) were exposed to hyperoxia and 70 (58.8%) were not during the first 24 hours after the CA. Those exposed had longer delays to return of spontaneous circulation (26 minutes vs. 10 minutes) and a longer interval to ICU admission after the arrest (4 hours compared to 1 hour). Location of the arrest was an independent predictor of exposure to hyperoxia (P-value = 0,008) with out-of-hospital cardiac arrest patients being more likely to have been exposed (65%), than those with an in-hospital (21%) or ICU (30%) cardiac arrest. Out-of-hospital cardiac arrest patients had higher oxygen concentrations to the fraction of inspired oxygen ratios. CONCLUSIONS: Hyperoxia exposure was more common than previously reported and occurred more frequently in association with out-of-hospital cardiac arrest, longer times to ROSC and delays to ICU admission.

Incidence, predisposing factors, management and survival following cardiac arrest due to subarachnoid haemorrhage: a review of the literature.

INTRODUCTION: The prevalence of cardiac arrest among patients with subarachnoid haemorrhage [SAH], and the prevalence of SAH as the cause following out-of-hospital cardiac arrest [OHCA] or in-hospital cardiac arrest [IHCA] is unknown. In addition it is unclear whether cardiopulmonary resuscitation [CPR] and post-resuscitation care management differs, and to what extent this will lead to meaningful survival following cardiac arrest [CA] due to SAH. AIM: We reviewed the literature in order to describe; 1.The prevalence and predisposing factors of CA among patients with SAH 2.The prevalence of SAH as the cause of OHCA or IHCA and factors characterising CPR 3.The survival and management of SAH patients with CA. MATERIAL AND METHODS: The following sources, PubMed, CinAHL and The Cochrane DataBase were searched using the following Medical Subheadings [MeSH]; 1. OHCA, IHCA, heart arrest and 2. subarachnoid haemorrhage. Articles containing relevant data based on the abstract were reviewed in order to find results relevant to the proposed research questions. Manuscripts in other languages than English, animal studies, reviews and case reports were excluded. RESULTS: A total of 119 publications were screened for relevance and 13 papers were included. The prevalence of cardiac or respiratory arrest among all patients with SAH is between 3-11%, these patients commonly have a severe SAH with coma, large bleeds and evidence of raised intracerebral pressure on computed tomography scans compared to those who did not experience a CA. The prevalence of patients with SAH as the cause of the arrest among OHCA cases vary between 4 to 8% among those who die before hospital admission, and between 4 to 18% among those who are admitted. The prevalence of SAH as the cause following IHCA is low, around 0.5% according to one recent study. In patients with OHCA survival to hospital discharge is poor with 0 to 2% surviving. The initial rhythm is commonly asystole or pulseless electrical tachycardia. In IHCA the survival rate is variable with 0-27% surviving. All survivors experience brief cardiac arrests with short latencies to ROSC. CONCLUSION: Cardiac arrest is a fairly common complication following severe SAH and these patients are encountered both in the pre-hospital and in-hospital setting. Survival is possible if the arrest occurs in the hospital and the latency to ROSC is short. In OHCA the outcome seems to be uniformly poor despite initially successful resuscitation.

Development and evaluation of an influenza pandemic intensive care unit triage protocol.

OBJECTIVES: To develop an influenza pandemic ICU triage (iPIT) protocol that excludes patients with the highest and lowest predicted mortality rates, and to determine the increase in ICU bed availability that would result. DESIGN AND SETTING: Post-hoc analysis of a study evaluating two triage protocols, designed to determine which patients should be excluded from access to ICU resources during an influenza pandemic. ICU mortality rates were determined for the individual triage criteria in the protocols and included criteria based on the Sequential Organ Failure Assessment (SOFA) score. Criteria resulting in mortality rates outside the 25th and 75th percentiles were used as exclusion criteria in a new iPIT-1 protocol. The SOFA threshold component was modified further and reported as iPIT-2 and iPIT-3. MAIN OUTCOME MEASURE: Increase in ICU bed availability. RESULTS: The 25th and 75th percentiles for ICU mortality were 8.3% and 35.2%, respectively. Applying the iPIT-1 protocol resulted in an increase in ICU bed availability at admission of 71.7% ± 0.6%. Decreasing the lower SOFA score exclusion criteria to ≤6 (iPIT-2) and ≤4 (iPIT-3) resulted in an increase in ICU bed availability at admission of 66.9% ± 0.6% and 59.4 ± 0.7%, respectively (P < 0.001). CONCLUSION: The iPIT protocol excludes patients with the lowest and highest ICU mortality, and provides increases in ICU bed availability. Adjusting the lower SOFA score exclusion limit provides a method of escalation or de- escalation to cope with demand.